using Arch.Core;
using HSchool.Ai;
using HSchool.Content;
using HSchool.People;
using HSchool.Schedule;

namespace HSchool.Simulation.Tests;

public class LessonTeacherPresentTests
{
    private static readonly DateTime TuesdayMorning = new(2012, 4, 3, 6, 0, 0, DateTimeKind.Utc);
    private static readonly DateTime LessonStart = new(2012, 4, 3, 8, 30, 0, DateTimeKind.Utc);

    [Fact]
    public void PupilAndTeacherStanding_GainsSkill()
    {
        var (school, homeroom, pupilId, teacherId) = StaffedMath();
        using (school)
        {
            AdvanceTo(school, LessonStart);
            SetPlace(school, pupilId, homeroom);
            SetPlace(school, teacherId, homeroom);
            var before = SkillOf(school, pupilId, "Mathematics");

            LessonLearningSystem.Apply(school, 45);

            Assert.True(SkillOf(school, pupilId, "Mathematics") > before);
        }
    }

    [Fact]
    public void TeacherInAnotherRoom_DoesNotGain()
    {
        var (school, homeroom, pupilId, teacherId) = StaffedMath();
        using (school)
        {
            AdvanceTo(school, LessonStart);
            SetPlace(school, pupilId, homeroom);
            SetPlace(school, teacherId, "restroom-1");
            var before = SkillOf(school, pupilId, "Mathematics");

            LessonLearningSystem.Apply(school, 45);

            Assert.Equal(before, SkillOf(school, pupilId, "Mathematics"));
        }
    }

    [Fact]
    public void TeacherWalking_DoesNotGain()
    {
        var (school, homeroom, pupilId, teacherId) = StaffedMath();
        using (school)
        {
            AdvanceTo(school, LessonStart);
            SetPlace(school, pupilId, homeroom);
            SetPlace(school, teacherId, "corridor-1", path: [homeroom], remaining: 1.5f);
            var before = SkillOf(school, pupilId, "Mathematics");

            LessonLearningSystem.Apply(school, 45);

            Assert.Equal(before, SkillOf(school, pupilId, "Mathematics"));
        }
    }

    [Fact]
    public void MissingTeacherId_DoesNotGain()
    {
        var (school, homeroom, pupilId, _) = StaffedMath(teacherId: "nobody");
        using (school)
        {
            AdvanceTo(school, LessonStart);
            SetPlace(school, pupilId, homeroom);
            var before = SkillOf(school, pupilId, "Mathematics");

            LessonLearningSystem.Apply(school, 45);

            Assert.Equal(before, SkillOf(school, pupilId, "Mathematics"));
        }
    }

    [Fact]
    public void NoTeacher_LogsOncePerSubject()
    {
        var (school, homeroom, pupilId, teacherId) = StaffedMath();
        using (school)
        {
            AdvanceTo(school, LessonStart);
            SetPlace(school, pupilId, homeroom);
            SetPlace(school, teacherId, "restroom-1");

            LessonLearningSystem.Apply(school, 5);
            LessonLearningSystem.Apply(school, 5);

            var rows = school.DayLog
                .Where(row => row.PersonId == pupilId && row.Type == PersonLogTypes.LessonNoTeacher)
                .ToArray();
            Assert.Single(rows);
            Assert.Equal("Mathematics", rows[0].ThingDef);
            Assert.Equal(
                "урок без учителя: Математика",
                rows[0].Caption(school.Catalog!, "ru"));
        }
    }

    [Fact]
    public void HungryStillGainsLess_WhenTeacherIsPresent()
    {
        var (school, homeroom, firstId, teacherId) = StaffedMath();
        using (school)
        {
            var schoolClass = school.Roster!.Classes.First(row => row.PupilIds.Contains(firstId));
            var secondId = schoolClass.PupilIds.First(id => id != firstId);
            AdvanceTo(school, LessonStart);
            SetPlace(school, firstId, homeroom);
            SetPlace(school, secondId, homeroom);
            SetPlace(school, teacherId, homeroom);
            SetNeed(school, firstId, "Hunger", 0.2f);
            SetNeed(school, secondId, "Hunger", 1f);
            var hungryBefore = SkillOf(school, firstId, "Mathematics");
            var fullBefore = SkillOf(school, secondId, "Mathematics");

            LessonLearningSystem.Apply(school, 45);

            var hungryGain = SkillOf(school, firstId, "Mathematics") - hungryBefore;
            var fullGain = SkillOf(school, secondId, "Mathematics") - fullBefore;
            Assert.True(fullGain > 0);
            Assert.True(hungryGain > 0);
            Assert.True(fullGain > hungryGain);
        }
    }

    [Fact]
    public void WeakTeacher_GainsLessThanStrong()
    {
        var (school, homeroom, pupilId, teacherId) = StaffedMath();
        using (school)
        {
            AdvanceTo(school, LessonStart);
            SetPlace(school, pupilId, homeroom);
            SetPlace(school, teacherId, homeroom);
            SetSkill(school, teacherId, "Mathematics", 20);
            var beforeWeak = SkillOf(school, pupilId, "Mathematics");
            LessonLearningSystem.Apply(school, 45);
            var weakGain = SkillOf(school, pupilId, "Mathematics") - beforeWeak;

            SetSkill(school, pupilId, "Mathematics", beforeWeak);
            SetSkill(school, teacherId, "Mathematics", 80);
            var beforeStrong = SkillOf(school, pupilId, "Mathematics");
            LessonLearningSystem.Apply(school, 45);
            var strongGain = SkillOf(school, pupilId, "Mathematics") - beforeStrong;

            Assert.True(weakGain > 0);
            Assert.True(strongGain > weakGain);
        }
    }

    [Fact]
    public void MissingTeacherSkillKey_StillGains()
    {
        var (school, homeroom, pupilId, teacherId) = StaffedMath();
        using (school)
        {
            AdvanceTo(school, LessonStart);
            SetPlace(school, pupilId, homeroom);
            SetPlace(school, teacherId, homeroom);
            ClearSkill(school, teacherId, "Mathematics");
            var before = SkillOf(school, pupilId, "Mathematics");

            LessonLearningSystem.Apply(school, 45);

            Assert.True(SkillOf(school, pupilId, "Mathematics") > before);
        }
    }

    [Fact]
    public void TeacherSkill_DoesNotRescueAbsence()
    {
        var (school, homeroom, pupilId, teacherId) = StaffedMath();
        using (school)
        {
            AdvanceTo(school, LessonStart);
            SetPlace(school, pupilId, homeroom);
            SetPlace(school, teacherId, "restroom-1");
            SetSkill(school, teacherId, "Mathematics", 100);
            var before = SkillOf(school, pupilId, "Mathematics");

            LessonLearningSystem.Apply(school, 45);

            Assert.Equal(before, SkillOf(school, pupilId, "Mathematics"));
        }
    }

    private static (School School, string Homeroom, string PupilId, string TeacherId) StaffedMath(
        string? teacherId = null)
    {
        var (catalog, map) = Vanilla();
        var roster = RosterGenerator.Generate(catalog, map, schoolSeed: 1, "Russia", TuesdayMorning);
        var pool = ApplicantPool.Create(catalog, roster, schoolSeed: 1, "Russia", TuesdayMorning);
        var hired = Staffing.Hire(catalog, map, roster, pool, pool.Applicants[0].Person.Id, Staffing.TeacherPosition, 1_000_000f);
        Assert.Equal(StaffingError.None, hired.Error);
        roster = hired.Roster;
        pool = hired.Pool;
        var hiredId = roster.People.First(person => person.IsStaff).Id;
        var schoolClass = roster.Classes.First(row =>
            row.RoomId is "classroom-101" or "classroom-102" or "classroom-103" or "classroom-104");
        var school = School.Create(1, "Урок", TuesdayMorning, catalog, map);
        school.InstallPeople(roster, seed: 1, "Russia", pool);
        school.SetTimetable(new Timetable(
            [new LessonPlacement(schoolClass.Id, "Mathematics", teacherId ?? hiredId, schoolClass.RoomId, Day: 1, Period: 1)],
            []));
        school.ConfigurePresence(weekDays: 5, maxDecisionsPerTick: 10_000);
        var pupil = schoolClass.PupilIds
            .Select(id => school.Roster!.People.First(person => person.Id == id))
            .First(person => !person.Traits.Contains("Lazy"));
        return (school, schoolClass.RoomId, pupil.Id, hiredId);
    }

    private static void AdvanceTo(School school, DateTime until)
    {
        while (school.Clock.Time < until)
        {
            school.Tick(0.2d, 5d);
        }
    }

    private static void SetPlace(School school, string personId, string node, string[]? path = null, float remaining = 0f)
    {
        var query = new QueryDescription().WithAll<PersonIdentity, Presence>();
        school.World.Query(
            in query,
            (ref PersonIdentity identity, ref Presence presence) =>
            {
                if (identity.Id.Equals(personId, StringComparison.Ordinal))
                {
                    presence = new Presence(node, remaining, node, HeadingHome: false, path ?? []);
                }
            });
    }

    private static void SetNeed(School school, string personId, string need, float value)
    {
        var query = new QueryDescription().WithAll<PersonIdentity, PersonNeeds>();
        school.World.Query(
            in query,
            (ref PersonIdentity identity, ref PersonNeeds needs) =>
            {
                if (identity.Id.Equals(personId, StringComparison.Ordinal))
                {
                    needs.Values[need] = value;
                }
            });
    }

    private static float SkillOf(School school, string personId, string skill)
    {
        var value = float.NaN;
        var query = new QueryDescription().WithAll<PersonIdentity, PersonSkills>();
        school.World.Query(
            in query,
            (ref PersonIdentity identity, ref PersonSkills skills) =>
            {
                if (identity.Id.Equals(personId, StringComparison.Ordinal))
                {
                    value = skills.Values.GetValueOrDefault(skill);
                }
            });
        return value;
    }

    private static void SetSkill(School school, string personId, string skill, float value)
    {
        var query = new QueryDescription().WithAll<PersonIdentity, PersonSkills>();
        school.World.Query(
            in query,
            (ref PersonIdentity identity, ref PersonSkills skills) =>
            {
                if (identity.Id.Equals(personId, StringComparison.Ordinal))
                {
                    skills.Values[skill] = value;
                }
            });
    }

    private static void ClearSkill(School school, string personId, string skill)
    {
        var query = new QueryDescription().WithAll<PersonIdentity, PersonSkills>();
        school.World.Query(
            in query,
            (ref PersonIdentity identity, ref PersonSkills skills) =>
            {
                if (identity.Id.Equals(personId, StringComparison.Ordinal))
                {
                    skills.Values.Remove(skill);
                }
            });
    }

    private static (DefCatalog Catalog, MapLayout Map) Vanilla()
    {
        var root = Path.Combine(AppContext.BaseDirectory, "vanilla");
        var documents = new List<ContentDocument>();
        foreach (var path in Directory.EnumerateFiles(root, "*.*", SearchOption.AllDirectories))
        {
            if (!path.EndsWith(".jsonc", StringComparison.OrdinalIgnoreCase)
                && !path.EndsWith(".json", StringComparison.OrdinalIgnoreCase))
            {
                continue;
            }

            var relative = Path.GetRelativePath(root, path).Replace('\\', '/');
            documents.Add(new ContentDocument(CatalogLoader.CorePackId, relative, File.ReadAllText(path)));
        }

        var catalog = new CatalogLoader().Load([CatalogLoader.CorePackId], documents);
        var map = CatalogLoader.LastDefaultMap([CatalogLoader.CorePackId], documents);
        Assert.NotNull(map);
        return (catalog, map);
    }
}